Javascript Error: 'Cannot read property zero of undefined"

Question

I've found many "Cannot read property '0' of undefined"s but they all are very context specific - or I don't understand JS very well.

What I've tried is looking to other problems, but as said, they are all context-specific. Here is the code. The error is on ln 64, although it probably results from a mistyped function call. Please help.

To reproduce, after copy-pasting transpiler code into the console:

input = '!say ::hello'
parse(tokenize(input));

transpiler code:

//actually useful is down here

function type (s) {
    if (s[0] == '!') {
        return 'f'; //function
    } else if (s[0] == '?') {
        return 'e'; //end
    } else if (s[0] + s[1] == '::') {
        return 'p'; //parameter
    } else {
        return 'o'; //operator or other
    }
}

var output = [];





function parse (r) {
var i;
for (i = 0; i < r.length; i++) {
    var rv = new Array();
    var scopecmd = false;
    if (scopecmd == false) {
        if (type(r[i]) == 'f') {
            scopecmd = true;    
            var c = r[i];
            c = c.replace('!', '');
            rv.push(c)
        } else if (type(r[i]) == 'p') {
            var c = r[i];
            c = c.replace('::', '');
            rv.push(c);
        }
    } else if (scopecmd == true) {
        if (type(r[i]) == 'p') {
            var c = r[i];
            c = c.replace('::', '');
            rv.push(c);
        }
    } else if (scopecmd == true && type(r[i]) == 'f') {
        scopecmd = false;
        var i2;
            var m;
        for (i2 = 1; i2 <= rv.length - 1; i2++) {
            var m = m + rv[i2] + ',';
        }
        m = m + rv[rv.length];
        output.push(eval(rv[0]+'('+m+');'));
    }
}

var i;
for (i = 0; i <= output.length; i++) {
    eval(output[i]);
}
}
function tokenize (input) {
var r = new Array();
r = input.split(' ');
return r;
}